An essential part of an air traffic controller's job consists in monitoring the runway approach of airplanes on the radar screen of a display device and in intercommunicating with the pilot in order to guide the airplane into the intended approach path. In doing so, the particular conditions of the airport (airport parameters), the environment variables (e.g., wind) as well as the parameters of the specific airplane have to be considered. Moreover, other airplanes nearby have to be monitored in order to avoid dangerous situtations or collisions. To get a license or keep it, air traffic controllers have to prove to have monitored a certain number of approaches. Since it is often impossible to perform the training in normal air traffic, special flights are frequently made for air traffic controller training only, which is very expensive due to the high costs of a flying hour.
To guide the approach and flying manoeuvres, airports are equipped with radar devices which are arranged laterally adjacent the runway. These radar devices are connected to display devices in the approach control center. On a screen, the display devices display an approach line corresponding to an ideal approach which leads exactly, on a predetermined path, to the landing point at the beginning of the runway. The radar device detects radar targets in vertical planes (elevation) and horizontal planes (azimuth), and the elevation plane and the azimuth plane are simultaneously displayed in various representations on the display device. An approach line corresponding to an ideal approach is simultaneously displayed for each of the two planes. Upon appearance of the airplane as radar target on the screen of the display device, the air traffic controller can monitor the deviations of the airplane position from the (ideal) approach line with respect to elevation and azimuth and guide the pilot in such a manner that the airplane flies exactly along the approach line in both planes.
Conventional simulators for the training of air traffic controllers are exclusively adapted to generate simulation targets, i.e. artificially generated radar targets, simulating the airport environment and flying airplanes. The basic training of air traffic controllers can be made with such simulators, thereafter, however, the air traffic controllers have to be trained on a real airport with actually flying airplanes. Each air traffic controller gets his license only for the specific airport where his training has been performed. With known flight simulators, it is not possible to include the conditions of a real airport in the simulation training.
An essential prerequisite for the correspondence between the actual approach line and the approach line displayed on the screen of the display device is that the radar device is exactly adjusted with respect to the runway. The vertical axis of the radar device, for example, which, at the same time, constitutes the rotational axis, has to be positioned with high accuracy. The rotation of the radar antennas with respect to the stationary coordinate system also has to be performed with high angular accuracy. Upon the assembly of radar devices, a highly accurate adjustment of the positions of the radar device and the various axes is performed. If the rotational angle deviates by only some tenths of a degree, this results in an erroneous determination of the extension of the runway axis. Since the adjustment of radar devices may become inaccurate in the course of time, frequent checking of the adjustment is required, for which purpose highly accurate measurements have to be performed. If misadjustments and/or deviations are detected, readjustments have to be made.
A conventional radar target simulator is known from German Patent Application DE 30 16 033 A1. This radar target simulator serves for causing lasting disturbances of the radar image as are caused by the opponent in electronic combats. The purpose of these disturbances is to prepare the operator of the radar device for disturbance situations by intensive training in order to be able to take adequate countermeasures. The simulation apparatus includes a ROM wherein the parameters of the flight route of an artificial target are stored as a function of time. The artificial targets are established by means of a computer without any cooperation of the simulator and are available in the form of a data carrier. The ROM modules of the simulator are programed with these data carriers. The motion paths of the artificial targets are fixed.